Tremolo devices have been used for many years with stringed musical instruments for creating a vibrato sound. Various structures have been proposed and utilized in the prior art for this purpose.
Broadly, a tremolo mechanism provides a means for changing the tension on all of the strings of the instrument simultaneously to create a pitch change during vibration of the strings. Typically, on many such string instruments as guitars, the bridge is mounted for enabling manual pivoting to thereby simultaneously change the pitch (tension) of all the strings to produce a vibrato effect, which is a steady oscillating variation of pitch about a primary frequency being perhaps the frequency most frequently used by guitarist. That is, each string has a primary tension, at which it has a desired primary pitch or tone. In such mechanism, the bridges are pivotally mounted to the instrument body and are maintained in a normal, string tensioned position by strong springs against the tension of the strings. A lever mounted to the bridge enables the instrument player to pivot the bridge and thus either increase the tension of each string above its primary tension to increase its pitch or relax it from its primary tension to decrease its pitch. Upon release of the lever, the springs return the bridge to the normal, static position for which the instrument is tuned.
A disadvantage with such prior art tremolo device is that the repeated and often violent tensioning and relaxing of the strings by operation of the bridge during playing of the instrument increases the friction in the tremolo device, preventing the strings from returning to their primary tension and pitch values and thus making it difficult for the instrument to be kept in tune. Furthermore, the life of the bridge is substantially decreased as it is continuously subjected to such pivoting action during desired production of a vibrato effect.
Another disadvantage encountered with prior art tremolo devices deals with the importance that the strings keep fixed positions relative to their strings supporting surfaces in order to maintain correct primary pitches. When the strings are at their primary tensions and pitches the force existing between each string and its string supporting surface tends to hold the string at a fixed position on the supporting surface. However, when the lever on the tremolo device is pivoted to relax the tension of the strings the force existing between each string and its string supporting surface is also reduced. Therefore, when this occurs a string may shift laterally away from its original position on its string supporting surface, and when the performer releases the lever the string may retain its laterally displaced position causing it to be de-tuned. Such situation is likely to occur when the tremolo device is operated to produce sound effects where the string tensions are relaxed to such degree that the strings become completely free of tension so as to be loose and able to move in a floppy manner relative to the tremolo device and other parts of the guitar.
Yet another disadvantage with prior art tremolo devices is that the strings are mounted on the bridge in such a manner so as to cause the tuning of the strings to be affected by pressure exerted thereof when musicians rest their hand or forearm on the bridge.
Accordingly, it is a primary object of the present invention to provide a tremolo device for stringed instruments which allows for the reduction of friction on the tremolo device to be reduced to the lowest possible amount permitting the strings to return to primary tension and pitch values.
It is a further object of the invention is to provide a tremolo device which avoids the possible de-tuning of the strings resulting from temporary relaxation of the string tensions through operation of the tremolo device.
Another object of the invention is to obviate the pressure exerted on the bridge from the musician's hand or forearm when rested thereon from affecting the tuning of the strings.
Additional objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description or be learned by practice of the invention.